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ARD Online First, published on March 4, 2015 as 10.1136/annrheumdis-2014-206917 Clinical and epidemiological research
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Gout and the risk of Alzheimer’s disease: a population-based, BMI-matched cohort study Na Lu,1,2 Maureen Dubreuil,1,3 Yuqing Zhang,1 Tuhina Neogi,1 Sharan K Rai,4 Alberto Ascherio,5 Miguel A Hernán,5 Hyon K Choi2 Handling editor Tore K Kvien ▸ Additional material is published online only. To view please visit the journal online (http://dx.doi.org/10.1136/ annrheumdis-2014-206917). For numbered affiliations see end of article. Correspondence to Hyon K Choi, Division of Rheumatology, Allergy, and Immunology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Bulfinch 165, Boston, MA 02114, USA; [email protected] Received 31 October 2014 Revised 16 December 2014 Accepted 13 January 2015
ABSTRACT Objective While gout is associated with cardiovascular (CV)-metabolic comorbidities and their sequelae, the antioxidant effects of uric acid may have neuroprotective benefits. We evaluated the potential impact of incident gout on the risk of developing Alzheimer’s disease (AD) in a general population context. Methods We conducted an age-matched, sex-matched, entry-time-matched and body mass index (BMI)-matched cohort study using data from The Health Improvement Network, an electronic medical record database representative of the UK general population, from 1 January 1995 to 31 December 2013. Up to five non-gout individuals were matched to each case of incident gout by age, sex, year of enrolment and BMI. We compared incidence rates of AD between the gout and comparison cohorts, excluding individuals with prevalent gout or dementia at baseline. Multivariate hazard ratios (HRs) were calculated, while adjusting for smoking, alcohol use, physician visits, social deprivation index, comorbidities and medication use. We repeated the same analysis among patients with incident osteoarthritis (OA) as a negative control exposure. Results We identified 309 new cases of AD among 59 224 patients with gout (29% female, mean age 65 years) and 1942 cases among 238 805 in the comparison cohort over a 5-year median follow up (1.0 vs 1.5 per 1000 person-years, respectively). Univariate (age-matched, sex-matched, entry-time-matched and BMI-matched) and multivariate HRs for AD among patients with gout were 0.71 (95% CI 0.62 to 0.80) and 0.76 (95% CI 0.66 to 0.87), respectively. The inverse association persisted among subgroups stratified by sex, age group (
ARD Online First, published on March 4, 2015 as 10.1136/annrheumdis-2014-206917 Clinical and epidemiological research
EXTENDED REPORT
Gout and the risk of Alzheimer’s disease: a population-based, BMI-matched cohort study Na Lu,1,2 Maureen Dubreuil,1,3 Yuqing Zhang,1 Tuhina Neogi,1 Sharan K Rai,4 Alberto Ascherio,5 Miguel A Hernán,5 Hyon K Choi2 Handling editor Tore K Kvien ▸ Additional material is published online only. To view please visit the journal online (http://dx.doi.org/10.1136/ annrheumdis-2014-206917). For numbered affiliations see end of article. Correspondence to Hyon K Choi, Division of Rheumatology, Allergy, and Immunology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Bulfinch 165, Boston, MA 02114, USA; [email protected] Received 31 October 2014 Revised 16 December 2014 Accepted 13 January 2015
ABSTRACT Objective While gout is associated with cardiovascular (CV)-metabolic comorbidities and their sequelae, the antioxidant effects of uric acid may have neuroprotective benefits. We evaluated the potential impact of incident gout on the risk of developing Alzheimer’s disease (AD) in a general population context. Methods We conducted an age-matched, sex-matched, entry-time-matched and body mass index (BMI)-matched cohort study using data from The Health Improvement Network, an electronic medical record database representative of the UK general population, from 1 January 1995 to 31 December 2013. Up to five non-gout individuals were matched to each case of incident gout by age, sex, year of enrolment and BMI. We compared incidence rates of AD between the gout and comparison cohorts, excluding individuals with prevalent gout or dementia at baseline. Multivariate hazard ratios (HRs) were calculated, while adjusting for smoking, alcohol use, physician visits, social deprivation index, comorbidities and medication use. We repeated the same analysis among patients with incident osteoarthritis (OA) as a negative control exposure. Results We identified 309 new cases of AD among 59 224 patients with gout (29% female, mean age 65 years) and 1942 cases among 238 805 in the comparison cohort over a 5-year median follow up (1.0 vs 1.5 per 1000 person-years, respectively). Univariate (age-matched, sex-matched, entry-time-matched and BMI-matched) and multivariate HRs for AD among patients with gout were 0.71 (95% CI 0.62 to 0.80) and 0.76 (95% CI 0.66 to 0.87), respectively. The inverse association persisted among subgroups stratified by sex, age group (
